Note 14 - Stock-based Compensation (Tables)

12 Months Ended

Dec. 31, 2012

Schedule of Share-based Compensation, Stock Options, Activity [Table Text Block]

						Weighted average
				Weighted		remaining
	Number of			average		contractual life		Aggregate
	options			exercise price		(years)		intrinsic value
Shares issuable under options - December 31, 2009		1,655,000		$	18.22
Granted		520,000			19.15
Exercised		(311,950	)		14.59
Forfeited		(12,750	)		16.23
Shares issuable under options - December 31, 2010		1,850,300		$	19.03
Granted		308,000			30.78
Exercised		(262,750	)		19.87
Shares issuable under options - December 31, 2011		1,895,550		$	20.83
Granted		367,000			31.48
Exercised		(363,850	)		19.15
Expired		(169,500	)		32.38
Shares issuable under options - December 31, 2012		1,729,200		$	22.31		2.37	$	12,228
Options exercisable - End of period		790,850		$	18.42		1.58	$	8,071

Stock Options Exercised {Table Text Block]

	2012		2011		2010
Number of options exercised		363,850		262,750		311,950
Aggregate fair value	$	11,198	$	8,510	$	6,741
Intrinsic value		4,265		3,320		2,190
Amount of cash received		6,933		5,190		4,551
Tax benefit recognized	$	1,438	$	1,119	$	699

Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions [Table Text Block]

	2012			2011			2010
Risk free rate		0.4	%		1.0	%		1.4	%
Expected life in years		4.75			4.75			4.75
Expected volatility		40.3	%		39.4	%		39.8	%
Dividend yield		0.0	%		0.0	%		0.0	%
Weighted average fair value per option granted	$	10.87		$	10.73		$	6.85